Description
An ETSI Technical Report (ETR) is a category of document produced by the European Telecommunications Standards Institute (ETSI). Unlike ETSI Standards (ESs) or ETSI Technical Specifications (TSs), which contain normative requirements that must be followed for compliance, an ETR is an informative document. Its primary purpose is to record technical investigations, feasibility studies, state-of-the-art analyses, or to provide guidance and technical explanations that support the standardization process. ETRs are published as part of ETSI's work program and are assigned a unique document number (e.g., ETR 300).
In terms of content and structure, an ETR typically follows a report format. It may begin with a scope and introduction, followed by detailed technical chapters presenting research findings, analysis of technologies, survey results, or tutorial information. It often includes comparisons of different technical approaches, identifies pros and cons, and may conclude with recommendations for future standardization work. Because they are not normative, ETRs do not use 'shall' statements that define mandatory behavior. Instead, they use 'may', 'should', or descriptive language. They are developed within ETSI's Technical Bodies (TBs), such as working groups, following ETSI's defined drafting and approval procedures.
Its role in the 3GPP and broader telecommunications ecosystem is that of a foundational or supporting document. Many concepts that eventually become core parts of 3GPP specifications are first explored and documented in ETRs. For example, early studies on new radio technologies, network architectures, or service frameworks might be captured in an ETR. These reports provide valuable context, historical record, and technical rationale that inform the subsequent development of normative standards. They are essential reference materials for engineers, researchers, and students seeking to understand the 'why' behind certain technical decisions or the evolution of a technology. While 3GPP produces its own Technical Reports (TRs), the term ETR specifically denotes those published directly by ETSI, which may include work that feeds into or complements 3GPP activities.
Purpose & Motivation
The ETR exists to fulfill a critical need in the standardization lifecycle: the need for a formal vehicle to publish informative, non-normative technical work. Not all valuable technical output is suitable for inclusion in a binding standard. Early-stage research, exploratory studies, and tutorial material are essential for building consensus and knowledge but do not constitute implementable specifications. Without a document type like the ETR, this work might remain as internal meeting notes or informal reports, lacking permanence, formal review, and wide dissemination.
The ETR solves the problem of knowledge capture and sharing during the pre-standardization and research phases. It allows standards bodies to document the technical reasoning behind decisions, archive alternative solutions that were considered but not adopted, and provide educational material for implementers. This is crucial for maintaining the transparency and continuity of complex, long-term standardization projects like 3GPP's generational releases. It ensures that the intellectual work invested in feasibility studies is not lost and can be referenced by future work items.
The creation of the ETR document type was motivated by the structured, multi-phase approach to standardization employed by ETSI and similar bodies. It formalizes the process of 'study before standardize'. By having a distinct deliverable, it clearly signals to the industry the status of the content—informative versus normative—managing expectations for implementers. It supports the efficient development of high-quality normative standards by ensuring that foundational technical questions are thoroughly investigated and documented before commitment to a specific technical solution in an ES or TS.
Key Features
- Informative, non-normative publication from ETSI
- Used for feasibility studies, technical surveys, and state-of-the-art reports
- Provides guidance, explanations, and technical rationale
- Assigned a unique ETR document number (e.g., ETR xxx)
- Developed and approved within ETSI Technical Bodies
- Serves as a precursor or supporting document for formal standards
Evolution Across Releases
The term 'ETR' (ETSI Technical Report) was formally referenced in 3GPP vocabulary (TS 21.905). This inclusion acknowledged ETSI's role as a partner standards body within the 3GPP project and established the ETR as a recognized type of external document relevant to 3GPP's work.
Defining Specifications
| Specification | Title |
|---|---|
| TS 21.905 | 3GPP TS 21.905 |